How fast does a object have to travel threw air before it will start to burn into a flame of fire?

like if a rock fell from the sky and starts to burn up.How fast does a object have to travel threw air before it will start to burn into a flame of fire?
Short answer: 93,600mph





Every object can only fall so fast. The highest speed it can reach is it's terminal velocity. When its weight is matched by air speed.


But to cause enough friction I'd say...


well meteors go at 93,600mph and they burn to smithereens!


So about 26 mile per second!How fast does a object have to travel threw air before it will start to burn into a flame of fire?
Depends on what it's made of. When the speed reaches a point that friction causes it to heat suffciently, it will ignite.





The Space Shuttle, for example, uses a material that is 'ablative', or inert. However, a piece of iron-nickel asteroid would heat much faster.
This also depends on the density of the air. The more dense the air, the slower the speed. The speed is relative to the conditions. Meteorites travel anywhere from 12-70 km/s.
A bullet is slow compared to a meteor, by a factor of about 17.
It really depends on how much it weighs and what it is.
depends on what it is made of.